OM3023 10/00 Operation - Section 3 Operating Instructions Page 3-23 ASR OPERATION Even if the ABS/ASR system is installed, the emergency brake function is maintained. If the ABS/ASR main switch is turned on with the brake pedal depressed or the retarder control lever pulled, exhaust sound will be momentarily emitted from the ABS valve. This does not indicate a fault. Turn on the trouble shooting switch only when performing trouble shooting on the truck. The ABS/ASR system will not function while the trou- ble shooting switch is turned on. If both rear wheels slip at the same speed, the ASR will not function, In this case, adjust the engine output with the accelerator pedal.
When installing a wireless device on the truck, select one which does not violate the wireless device-related laws/regulations and use it according to law. Mount it as far away from the devices and harness of the ABS/ASR system as possible. 1. Since the ASR and ABS are interlocked, if the ABS is turned on, the ASR is also turned on automatically. 2. The ASR information lamp lights up when the system detects slippage of the rear wheels, and the ASR starts functioning. PRECAUTIONS FOR USE TROUBLESHOOTING When the key switch is turned on, if the warning lamp (1, Figure 3-3) does not light up, it may be defective. In this case, replace the lamp.
If the ABS functions while traveling on a slippery road, the braking distance may be slightly length- ened. Even if the ABS is turned on, the tires may lock when the truck is braked when running at a very low speed. Accordingly, take care when driving on slippery roads. If the ABS/ASR system malfunctions while being used, the warning lamp (Red) will light up. In this case, stop the truck at a safe place immediately, then notify the maintenance department. If the truck is braked while running at high speed or on a slippery road, more air is consumed by the ABS/ASR. If the air pressure drops and the warning buzzer sounds, stop the truck in a safe place.
Wait until the air pressure is restored suffi- ciently in the safe zone, then proceed again. The positions of each switch and the status of the corresponding warning lamp are as follows: Even with the ABS/ASR system installed, there may be instances where the truck can not travel safely such as on a road having an extremely low coefficient of friction (a frozen road, etc.) or on a steep slope. In this case, repair the road surface before driving. The truck can be driven normally even if the ABS/ ASR main switch is turned off. In this case, however, watch out for lateral skidding of the truck. Even if the ABS/ASR system malfunctions, the truck can be driven normally.
Watch out for lateral skidding in this case, however, while driving on slippery roads, If the warning lamp lights up, the system is automatically turned off and the ABS/ ASR system does not function. Key Switch ABS/ASR Switch Warning Lamp OFF OFF Turns OFF OFF ON Turns OFF ON OFF ON (Normal) ON ON • Stays ON, until travel speed rises above 10 km/h (6.2 MPH), then turns OFF (Normal) • Turns ON when a fault occurs (Malfunction)